Bad news for X users, with the company admitting a “security incident” may have left some people’s likes public, instead of keeping them private.

X announced in mid-June that it was making likes private for everyone in an effort to cut down on bullying. Owner Elon Musk indicated the move was to allow people to like content they might otherwise be reluctant to, for fear of being attacked for their views.

Unfortunately, according to 9to5Mac, X has been sending emails out to some users to let them know their likes may not have been private after all.

“The X team received information that some likes may have remained publicly available,” reads the email. “We have contacted you because your X account may have been potentially affected by this security incident.”

It’s unclear what the “security incident” was, or what led to it.